Remove stem end and tough outer leaves from lemon grass. Cut inner stalk into chunks; put in a food processor with cilantro, garlic, salt, turmeric, and pepper. Whirl until finely minced. Pat mixture over chicken wings. Cover and chill at least 1 hour or up to 1 day.
Lay chicken wings on a lightly oiled barbecue grill over a solid bed of medium coals or medium heat on a gas grill (you can hold your hand at grill level only 4 to 5 seconds); close lid on gas grill. Cook chicken, turning occasionally, until no longer pink at the bone (cut to test), about 15 minutes total. Transfer to a platter. Serve with Cucumber Salad.